Method for operating a drive unit comprising an internal combustion engine and an electric machine and drive unit for carrying out such a method

Abstract

The description relates to a method for operating a drive unit comprising an internal combustion engine, which is at least drive-connectable to an electric machine which delivers power to a drive train or receives power, and comprising at least one automatically actuable clutch, wherein the electric machine is at least drive-connectable to a manually shiftable transmission of the drive train, the manually shiftable transmission is shiftable without actuation of a clutch.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application claims priority to German Patent Application No. 102017215854.9, filed Sep. 8, 2017. The entire contents of the above-referenced application are hereby incorporated by reference in their entirety for all purposes.BACKGROUND AND SUMMARY[0002]When developing drive units for vehicles, attempts are constantly being made to minimize fuel consumption. The aim is moreover to reduce pollutant emissions so that it is possible to observe future limit values for pollutant emissions. Therefore, according to the prior art, an electric drive is used more and more frequently in vehicles—generally in combination with an internal combustion engine as a hybrid drive.[0003]In terms of lowering fuel consumption or reducing pollutant emissions, this is only advantageous if the electric drive has a greater efficiency in at least one operating range or engine map range than the internal combustion engine and therefore an advantage over the inter...

AI Technical Summary

Benefits of technology

[0009]A drive unit comprising an internal combustion engine and an electric machine is generally also referred to as a hybrid drive. In the present case, as a drive unit for driving a vehicle, it is possible to use the electric machine exclusively in a two-pedal mode and the internal combustion engine exclusively in a three-pedal mode. However, it is also possible to use and operate the electric machine as a drive simultaneously along with the internal combustion engine. Both the internal combustion engine and the electric machine then deliver power to the drive train.

[0010]The present description may provide several advantages. In particular, the approach may improve drivetrain efficiency. Further, the approach may improve ease of driving a vehicle. Additionally, the approach may improve a human driver's confidence of operating a manual transmission.

Problems solved by technology

The noise emissions of a motor vehicle, in particular the drive noises, not only have a disadvantageous effect on the quality of life or the wellbeing of people exposed to the noise, but also on their health, which is why a multitude of regulations have been established which stipulate the noise limit values to be observed.

However, the lack of drive noise of an electric drive also has disadvantages.

If the electric machine is used as a drive unit in the two-pedal mode, the driver, owing to the lack of combustion noise from the internal combustion engine, is uncertain and uninformed as to whether and when it is necessary or advisable to shift transmission gears, i.e. when the gear should—preferably—be changed by manually shifting the transmission.

As a result, the potential offered by a hybrid drive remains at least periodically and at least partially unused.

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